Journal of Chemical Physics, Vol.101, No.1, 814-821, 1994
Modeling and Analysis of Moving Temperature Patterns on Catalytic Surfaces
A mathematical model that predicts moving temperature and concentration patterns on nonisothermal catalytic surfaces is developed and analyzed. The model accounts for a slow change of the surface activity of the catalyst, diffusion of the species, conduction of heat, convection from the fluid phase, and a Langmuir-Hinshelwood-type kinetic expression. It is shown that this model predicts ignition, extinction, and homogeneous oscillations for a wide range of parameter values. It is found that the model does not predict stationary temperature patterns for typical values of the transport coefficients. However, the model predicts moving (oscillating) temperature and concentration patterns for typical parameter values. The calculations show that these spatiotemporal patterns exist in regions near the homogeneous Hopf bifurcation point indicating that homogeneous oscillations are unlikely to occur. It is also found that the typical size of these moving patterns is of the order of 1 cm(2) and the period of oscillation is smaller but of the same order of magnitude as the period of homogeneous oscillation.